Typewriting machine



March 11, 1930. L. c. MYERS TYPEWRITING MACHINE Filed 001;. 10, 1927Patented Mar. 11, 1930 UNITED STATES PATENT OFFICE LEWIS C. MYERS, OFFREEPORT, NEW YORK, ASSIGNOR TO ROYAL TYPEWRITER COMI- PANY, INC., OFNEW YORK, N. Y., A CORPORATION OF NEW YORK 'rxrnwnrrino MACHINE 1Application filed October 10, 1927. Serial No. 225,328.

This invention relates to fractional line space mechanism or line spacerelease mechanism in which the platen is disconnected from the linespace ratchet wheel and may be turned independently thereof through anydesired distance and again connected to the ratchet wheel at the end ofthe turning movement.

An object of the invention is to provide a very simple and compactmechanism for this purpose which is particularly adapted for the Royalportable machine in connection with which it is illustrated, but whichmay be applied to other types of machines if desired. I

In the drawings:

Figure 1 is a longitudinal section through the end of the platen andconnected parts with the ratchet wheel connected to turn with theplaten.

Figure 2 is a similar view with the ratchet wheel disconnected from theplaten.

Figure 3 is an end view of the platen head with a portion of the releasemechanism.

Figure 4 is a detail view of the engaging teeth of the release mechanismon a greatly enlarged scale.

Figure 5 is a side elevation and end view of one end of the platen axle.

A platen axle A is mounted in the platen of a typewriter carriage Bwhich may be of any usual or desired construction. This platen has theusual outer rubber layers C and C and a wooden core D. A finger wheel Eis attached to the end of the axle and a ratchet line space wheel F ofthe usual character is provided.

The platen head 1 is connected to the wooden core D by screws 2 orsimilar fastenings and this head has an inwardly extending hub 3 havinga hollow portion in which is positioned a coil spring 4. A cup-shapedclutch member 5 including a peripheral flange is loosely mounted ontheplaten axle and carries the ratchet wheel F. A portion of the innerperiphery of the flange of this cupshaped member is provided with anannular row of fine teeth 6.

Fastened to the platen head 1 is a plurality of outwardly projectingheaded studs 7 on which is slidably mounted a clutch plate 8 ofgenerally triangular shape which has a plurality of outer projectingportions provided with fine teeth 9 which are arranged concentrically ofthe axle A and are adapted to engage the internal teeth 6 when the partsare in the Figure 1 position. At this time a turning of the ratchetwheel F will rotate the cup-shaped member 5 and through the engagingteeth 6 and 9 will rotate the plate 8 which in turn through the studs 7transmits the rotary movement to the platen head 1 and the platen. Arelease plate 10 lies on the outer face of the plate 8 and is providedwith cut-outs or slots as clearly shown in Figure 3, which engage thestuds 7 and hold the plate 10 in position. The release plate issubstantially triangular in outline and is slidably mounted on the studs7 and bears against the face of the clutch plate 8 opposite the platenhead. There are three slots formed in the release plate and these slotsare respectively locatedin the apices of the plate. Two of the slotsextend inwardly from adjacent sides of the plate and the third slotextends inwardly from its associated apex to form a seat for the plate.The first two slots are curved in an arc concentric with the seatwhereby the plate may be swung about said seat into and out ofengagement with the studs. It is additionally held in the desiredposition by means of an car 11 which is bent into an opening 12 in theplate 8 as clearly shown in Figurel. An ear 11 functions to retain therelease plate 10 against being accidentally swung on the seat referredto above, and consequently this ear functions to retainthe release platein cooperative engagement with the studs 7.

The outer end of the platen axle A is provided with a longitudinalgroove 13 as shown in Figure 5 and a tongue 14 of the release plate 10projects into this groove in position to be engaged by the inner end ofa plunger 15 lying in the groove of the axle and coaxial therewith,which plunger is provided at its outer end with a finger piece 16 andhas a collar 17 which limits its movement in either direction andprevents accidental removal thereof. The finger wheel E is cut away on Iits outer face so that the finger piece 16lies in the cut away portionand does not project beyond the edge of the finger wheel E.

Assuming that the parts are in the Figure 1 position and it is desiredto release the platen from the line space wheel F which wheel it will beunderstood may be actuated by any suitable line space pawl as desired,the operator will exert pressure on the finger piece 16, moving theplunger 15 inwardly and since the inner end'of the plunger engages thetongue 14 of the release plate 10,

this plate and the clutch plate 8 will be given a sliding movement onthe studs 7 to the Figure 2 position in which the teeth 9 have beenmoved out of engagement with the teeth '6 of the clutch cup or member 5and the platen may be turned independently of the line space mechanism.When the platen has been moved to its desired position, the finger piece16 will be released and the spring 4 will return the parts to the Figure1 position.

It will be observed that the invention comprises a very simple andcompact arrangement which involves the use of a much smaller number ofparts than is usually the case with platen release mechanisms. It isalso evident that certain details of construction clutch teeth, a clutchplate surrounding the axle and mounted on the studs for relative slidingmovement thereon and provided with teeth for engaging the teeth of theclutch member, a single coil spring surrounding the axle and locatedbetween the platen head and the clutch plate for yieldably retainingsaid plate in clutched engagement with the clutch member, and manuallyoperable means for moving the clutch plate against the tension of thesingle spring for disengaging said plate from the clutch member.

2. In a fractional line spacing mechanism for typewriting machines, thecombination with an axle, of a platen freely journaled on said axle andincluding a head, a line space ratchet wheel journaled on the axle, andmeans for clutching the platen and wheel comprising studs immo vablyfixed to the platen head, a clutch cup movable with the ratchet wheeland including a peripheral flange surrounding the studs and having an 1annular series of inwardly projecting teeth,

a clutch plate surrounding the axle and mounted on the studs forrelative sliding movement thereon and provided with peripheral teeth forengaging the teeth of the clutch cup, a single coil spring surroundingthe axle and located between the platen head and the clutch plate foryieldably retaining said plate in clutched engagement with the clutchcup, and manually operable means for 7 moving the clutch plate againstthe tension of'the single spring for disengaging said plate from theclutch cup. 7

8. In afractional line spacing mechanism for typewriting machines, thecombination with an axle having a longitudinal groove at one endthereof,of a platen freely journaled on said axle and including a head locatedadjacent the groove, a line space-ratchet wheel journaled on theaxle,and means for clutching the platen and wheelecomprising studs immovablyfixed to the platen head and arranged in triangular formation, a clutchcup movable with the ratchet wheel and including a peripheral flangesurrounding the studs and having an annular series of inwardlyprojecting teeth, a clutch plate surrounding the axle and mountedon" thestuds for relative sliding movement thereon and provided with peripheralteeth for engaging the teeth of the clutch cup, means located betweenthe platen head and the clutch plate for yieldably retaining said platein clutched engagement with the clutch cup, and manually operable meansmounted in the groove of the axle for moving the clutch plate againstthe tension of the yieldable means for disengaging said plate fromtheclutch cup. V

4:. In a fractional line spacing mechanism for typewriting machines, thecombination with an axle having a longitudinal groove at one endthereof, of a platen freely journaled on said'axle and including a headlocated adjacent the groove, arline space ratchet wheel journaled on theaxle, and means for clutching the platen and wheel comprising studsfixed to the platen head and arranged in triangular formation, a clutchmember movable with the ratchet wheel and having a plurality of clutchteeth, a clutch plate surrounding the axle and mounted .on the studs forrelative sliding movement and provided with teeth for engaging theteeth-of the clutch member, a release plate slidably mounted on thestuds and bearing against the face of the clutch plate opposite theplaten head, said release plate being provided with a tongueprojectinginto the'groove of the axle, means located between the platen head andthe clutch plate for yieldably retaining said clutch plate in clutchedengagement with the clutchmember, and a manually operable plungermounted in the groove of the axle and engageable with thetongue of therelease plate for moving the clutch plate against the tension of theyieldable means for disengaging said plate from the clutch member.

5. In a fractional line spacing mechanism for typewriting machines, thecombination with an axle having a longitudinal groove at one endthereof, of a platen freely journaled on said axle and including a headlocated adjacent the groove, a line space ratchet wheel journaled on theaxle, and means for clutching the platen and wheel comprising studsfixed to the platen head and arranged in triangular formation, a clutchcup movable with the ratchet wheel and including a pcripheral flangesurrounding the studs and having an annular series of inwardlyprojecting teeth, a clutch plate surrounding the axle and mounted on thestuds for relative sliding movement and provided with peripheral teethfor engaging the teeth of the clutch cup, a substantially triangularrelease plate slidably mounted on the studs and bearing against the faceof the clutch plate opposite the platen head, said release plate beingformed in its apices with three slots for receiving the studs, two ofthe slots extending inwardly from adjacent sides of the plate and thethird slot extending inwardly from the apex to form a seat for theplate, the first two slots being curved in an are concentric with saidseat whereby said plate may be swung about said seat into and out ofengagement with said studs, said release plate being provided with atongue projecting into the groove of the axle, means located between theplaten head and the clutch plate for yieldably retaining said clutchplate in clutched engagement with the clutch member,.and a manuallyoperable plunger mounted in the groove of the axle and engageable withthe tongue of the release plate for moving the clutch plate against thetension of the yieldable means for disengaging said plate from theclutch member.

6. In a fractional line spacing mechanism for typewriting machines, thecombination with an axle having a longitudinal groove at one endthereof, of a platen freely journaled on said axle and including a headlocated adjacent the groove, a line space ratchet wheel journaled on theaxle, and means for clutching the platen andwheel comprising studs fixedto the platen head and arranged in triangular formation, a clutch membermovable with the ratchet wheel and having a plurality of clutch teeth, aclutch plate surrounding the axle and mounted on the studs for relativesliding movement and provided with teeth for-engaging the teeth of theclutch member, said clutch plate being provided with an opening, arelease plate slidably mounted on the studs and bearing against the faceof the clutch plate opposite the platen head, said release plate beingprovided with a tongue projecting into the groove of the axle and withan ear projectengaging said plate from the clutch member.

In testimony whereof, I have hereunto subscribed my name.

LEWIS O. MYERS.

